What is the hose for that goes from the fuel pump to the one cylinder? Is that used for oil delivery to the crank? If not, how does the oil get to the crank? How does the fuel pump work internally? There is an in for oil and fuel. There is 3 lines coming out, two to carbs, one to cylinder. If I know my oil pump is good, and my line to the cylinder is dry, does that mean my fuel pump is bad?
horkn
New member
laidt said:
that is a vacuum line for the fuel pump.
daman
New member
Like said thats your vacuum pulse line it, runs your fuel pumplaidt said:
your crank gets oiled from the oil in the gaslaidt said:
Oil gets mixed IN the fuel pump(1 oil line in) then sent to each carb (two lines out)laidt said:
Here's the deal, after I put that used cylinder and piston in my sled, it lasted 400 miles and she died. I lost compression in the used cylinder, the one on the side that the hose connects to. When I took it apart, the rings were destroyed on the exhaust side of the piston. In turn, the cylinder and piston was destroyed as well as the head (from some metal piece hitting it). Well, after replacing the cylinder, piston, and rings, along with a good used head, she lasted about 15 minutes, the same side destroyed once again. My oil pump is new and was primed as the one cylinder is holding up fine. I will assume that something went bad in my carb? What else could it be? It's not antifreeze either. Can a carb be ran that lean that it can do this? What would make it fail after 400 miles?
I'm working thru a very similiar situation and need to find a few parts or used motors, hopefully you don't mind sending along info.
i've got 2) 98' twin 500 lc motors to repair or replace.
4) 500 cylinders
or
2) 500 cylinders
2) 600 cylinders and 1 600 head
i'll be getting new pistons and rings, anyone have experience and info on converting a 500 twin to a 600? does it require different carbs? and what about a 600 triple, it would seem you'd need at least new carbs, exhaust, ??
thanks
i've got 2) 98' twin 500 lc motors to repair or replace.
4) 500 cylinders
or
2) 500 cylinders
2) 600 cylinders and 1 600 head
i'll be getting new pistons and rings, anyone have experience and info on converting a 500 twin to a 600? does it require different carbs? and what about a 600 triple, it would seem you'd need at least new carbs, exhaust, ??
thanks
Which side? PTO or MAG.
Who are you asking which side? I assume PTO is power take off and Mag is magneto, my problem cylinder is the mag side.
I was just curious. When you rebuilt it did you check the condition of the crank seals?
I did not. Would that cause this failure? To me, it seems like the one cylinder is getting no oil, no lube. Does the crankshaft pick up oil off the bottom of the case? There was oil present on the case bottom on the PTO side but not the Mag side.
Oil is from the mix. Takes place in the fuel pump. Bad crank seal will cause the motor to run lean which = stuck piston. Take some pictures and post them up. There are lots of good motor guys on the site. They will point you in the right direction.
horkn
New member
laidt said:
oh yeah, a bad crank seal will toast a cylinder very quickly.
horkn
New member
laidt said:
in the case, between the upper and lower portions of the case. These are rubber (y) and can deteriorate, allowing the fialed seal to let air in, leaning that entire cylinder out.
http://www.portyamaha.com/fiche_section_detail.asp
part # 25 and 26 on the crankshaft section for the 97 600xtc. I think #20 is the center seal, that separates cylinder 1 from cyl 2.
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Would this motor work in my sled? It's a 600 from 96 and I have a 97.
http://cgi.ebay.com/ebaymotors/YAMA...016QQitemZ260247020608QQrdZ1QQsspagenameZWDVW
http://cgi.ebay.com/ebaymotors/YAMA...016QQitemZ260247020608QQrdZ1QQsspagenameZWDVW